Interesting take on colour perception TK, I always wondered about the blue rinse phenomenon, but isn’t it the other way round with age, I get the impression the older members here are the ones more likely to prefer the warmer, lower cct values?

Would an XPL {HI} 4D or 4C or 5A1/A2 or 5B1/B2, XPLAWT-H0-0000-000LV20E4
be of consideration for the emitter choice?

Anything above the blackbody line is probably not happening, because it would look green. So, no “B” or “C” tints.

Early poll results made 4A the top choice, but it shifted later so now the vote points toward 3D. That means 4D or 5A are unlikely unless Lumintop decides to offer a bunch of options like Emisar does. The data so far points toward 5000K (or slightly below) for XP-L HI and toward 4000K for LH351D.

This is a strange phenomenon that I have gathered some info while working in biology.

Apparently, cyan photoreceptors have a lower lifespan than magenta and yellow, because they tend to absorb higher frequency wavelengths, which are more energetic and destroy the photoreceptors more quickly than the others.

Therefore, with age, there is degeneration of the cyan photoreceptors resulting in lower sensitivity in the blue part of the visible light spectrum, meaning you see less intense blue as you age, explaining what Toykeeper said.

Anyway, this phenomenon also happens in OLED displays: being organic, the blue pixels degrade more quickly than red and yellow. This is why instead of an RGB stripe arrangement, we get Diamond Stripe Pixel arrangement. This allows for lower degradation, but a lower effective resolution.

Interesting take on colour perception TK, I always wondered about the blue rinse phenomenon, but isn’t it the other way round with age, I get the impression the older members here are the ones more likely to prefer the warmer, lower cct values?

Noooooooo….. may it never be. . .

I’m a ‘mature’ member (older) & with very rare exception, I detest pretty much anything below 5000K. A rare dip to 4500K is as low as it gets by choice.

Don’t like it to ‘cool’ either…. 5700K is about the upper limit for me.

2A . 2D . 3A . 3D

—

You never know how a horse will pull until you hook him up to a heavy load./"Bear" Bryant

Apparently, cyan photoreceptors have a lower lifespan than magenta and yellow, because they tend to absorb higher frequency wavelengths, which are more energetic and destroy the photoreceptors more quickly than the others.

Therefore, with age, there is degeneration of the cyan photoreceptors resulting in lower sensitivity in the blue part of the visible light spectrum, meaning you see less intense blue as you age, explaining what Toykeeper said.

True. My uncle was an eye surgeon and encouraged us to protect our eyes from UV at all times, even wear sunglasses always during full daylight.

The human eye doesn’t need full daylight to work properly, and the pupil can only contract so far to dim it down.

Lowers the chance of developing cataracts too.

Being short-sighted I’ve always had glasses on, with plastic lenses they block UV almost completely, so despite being older than some, I hope my colour perception is still reasonably OK.

Contact lenses aren’t so protective.

If you use a UV torch, always protect your eyes.

Living in Northern latitudes, mostly 50 degrees North, (but not under the ozone hole) probably helps as well.

It makes sense to me that those with older or simply worn-out eyes from long exposure to bright sunlight might prefer the higher colour temperatures, and have less preference for high CRI.

Wear your eyes out and you’ll also become less sensitive to lower light levels, many elderly have real trouble driving at night, almost blind.

The human eye was probably only “designed” to last 40 years or so and hasn’t evolved much since, so look after yours.

I very rarely use a torch in daylight, that’s probably why I prefer low colour-temp, high CRI, and high intensity is of less importance.

I carry a floody light for close range that is high CRi and high R9, and less than 5000k. I use less than 100 lumens indoors, and I prioritize High CRI for that. My indoor use targets are usually smaller and more detailed, and their color is more important to me, especially things like food.

and I carry a spotty light for outdoor distance, that is cooler and has less CRI and less R9 and is more than 5000k. I use more than 100 lumens for outdoor distance, and have less of a fixation on accurate color rendering,
because the target is usually larger, and I mostly just want to know if there is a bear there or not. Im less concerned with the color of the bear.

if the use scenario is to spot a bear, brighter spottier and cooler is better
if the use scenario is to prep food at camp, hang out indoors relaxing, less bright, floodier, and warmer is better, for me.

ymmv by use application

Im 65, wear glasses, have cataracts and other vision challenges, but old ladies with blue hair definitely do not look like blond barbies to me
I also dislike green tint, and 5000k+ low CRI lights have more green tint than my sub 5000k High CRI lights.
However I dont notice the green tint of my cooler lights when my brain is white balanced to cooler CCTs durig the day. I notice the green tint of 5000k+ lights more, when I am adapted to the incandescent light in my home at night.

Apparently, cyan photoreceptors have a lower lifespan than magenta and yellow, because they tend to absorb higher frequency wavelengths, which are more energetic and destroy the photoreceptors more quickly than the others.

Therefore, with age, there is degeneration of the cyan photoreceptors resulting in lower sensitivity in the blue part of the visible light spectrum, meaning you see less intense blue as you age, explaining what Toykeeper said.

True. My uncle was an eye surgeon and encouraged us to protect our eyes from UV at all times, even wear sunglasses always during full daylight.

The human eye doesn’t need full daylight to work properly, and the pupil can only contract so far to dim it down.

Lowers the chance of developing cataracts too.

Being short-sighted I’ve always had glasses on, with plastic lenses they block UV almost completely, so despite being older than some, I hope my colour perception is still reasonably OK.

Contact lenses aren’t so protective.

If you use a UV torch, always protect your eyes.

Living in Northern latitudes, mostly 50 degrees North, (but not under the ozone hole) probably helps as well.

It makes sense to me that those with older or simply worn-out eyes from long exposure to bright sunlight might prefer the higher colour temperatures, and have less preference for high CRI.

Wear your eyes out and you’ll also become less sensitive to lower light levels, many elderly have real trouble driving at night, almost blind.

The human eye was probably only “designed” to last 40 years or so and hasn’t evolved much since, so look after yours.

I very rarely use a torch in daylight, that’s probably why I prefer low colour-temp, high CRI, and high intensity is of less importance.

Also darker eye color is the major factor for low wear levels in the eye after a certain age. Dark pigments in iris tend to absorb light much more.

So if you have blue, green eyes they need to be protected 2X carefully.

I am opposite to jon on the CCT for indoor/outdoors; outdoors in a throwy light too cool of a color temperature is more than useless; it will make such a noticable beam in any haze at all that it is hard to see past it to the thing I want to look at. I would rather a neutral-warm color with fair to good rendering so that I can tell the difference as zak puts it “between a stick and a snake”; the better the color quality the less harsh and difficult to interpret its light seems to be, though actual brightness is not unimportant. Though for the most distance or for locating rogue helicopters or trees, I suppose even a low color quality will suffice.

FWIW, a sliced and sanded high CRI 4000K Samsung LG351D did warm up from 4000K to 3500K with a tint shift from slightly green to yellow-rosy, and a considerable throw increase, a clear sign that light recycling does happen in modern, warm tinted leds.

So is that a brown wall, brown shutter, and brown floor as the 4000K makes it look, or is there a white floor, blue/grey shutter and oatmeal wall, as the 5000K shows?

This is what makes me wonder why anyone has a preference for high cri in a warm cct, if it makes everything that does not have a stark colour look brown, what use is the cri? To me it is like having a magnificent variety in your exotic fish tank, and preferring to keep the water dirty.

Off white desk, greenish background to the left and grey to the right.

So is that a brown wall, brown shutter, and brown floor as the 4000K makes it look, or is there a white floor, blue/grey shutter and oatmeal wall, as the 5000K shows?

This is what makes me wonder why anyone has a preference for high cri in a warm cct, if it makes everything that does not have a stark colour look brown, what use is the cri? To me it is like having a magnificent variety in your exotic fish tank, and preferring to keep the water dirty.

Far too much green gum (how much do you chew ?)

Did you leave your camera on auto white balance ? Seems to have tried to keep the green gum green (typical behaviour, the natural world is mostly green, so digicams are biased to make it look so)

Not that this means much, use you’re eyes.

By the way, there is a lot more colour in the 4000K shot, even though it is completely wonky.

Camera set to 4500k manual settings for both shots. That gum is over a couple years.

Would an XPL {HI} 4D or 4C or 5A1/A2 or 5B1/B2, XPLAWT-H0-0000-000LV20E4
be of consideration for the emitter choice?

Anything above the blackbody line is probably not happening, because it would look green. So, no “B” or “C” tints.

Early poll results made 4A the top choice, but it shifted later so now the vote points toward 3D. That means 4D or 5A are unlikely unless Lumintop decides to offer a bunch of options like Emisar does. The data so far points toward 5000K (or slightly below) for XP-L HI and toward 4000K for LH351D.

Definitely good to hear no matter the LED (A and D are definitely my preference)

I personally want to try to choose the highest efficacy for eye-strain sensitive individuals such as myself, definitely planning on its use as a bike light around others.

Are you sure you want to use the FW3A as a bike light? There are much better choices out there.

Well Currently the D4 is my bike light, it used to be my wizard xD

IMO, lights that use FET drivers make poor choices for bike lights. I used to use a BLF A6 that uses a FET+1 driver, but in any bright mode (more than about 150 lumens) it dims as the battery drains. I know the FW3A is supposed to use more 7135 chips, but I don’t believe it will maintain constant output. All my Convoys that use 8×7135 chips, still dim significantly as the battery voltage goes down. Not as bad as FET, but still very noticeable. Maybe the FW3A will do things better than Convoy, but I wouldn’t rely on that.

I now use a Zebralight SC600w MkIV Plus as my bike light. I normally use it at 700 lumens, and that will provide me a regulated 700 lumen output for almost 3 hours (using a Sanyo GA cell). If I go up to 2300 lumens, it will go up that high, regardless of the battery voltage. And when going downhill on gravel or dirt, I want that full 2300 lumens.

You need a light with a good boost driver if you want regulated output. For me, that’s very important when cycling. I don’t want to start out at 700 lumens, only to have it gradually dim to 400 lumens over my ride.

I personally want to try to choose the highest efficacy for eye-strain sensitive individuals such as myself, definitely planning on its use as a bike light around others.

Are you sure you want to use the FW3A as a bike light? There are much better choices out there.

Well Currently the D4 is my bike light, it used to be my wizard xD

IMO, lights that use FET drivers make poor choices for bike lights. I used to use a BLF A6 that uses a FET+1 driver, but in any bright mode (more than about 150 lumens) it dims as the battery drains. I know the FW3A is supposed to use more 7135 chips, but I don’t believe it will maintain constant output. All my Convoys that use 8×7135 chips, still dim significantly as the battery voltage goes down. Not as bad as FET, but still very noticeable. Maybe the FW3A will do things better than Convoy, but I wouldn’t rely on that.

I now use a Zebralight SC600w MkIV Plus as my bike light. I normally use it at 700 lumens, and that will provide me a regulated 700 lumen output for almost 3 hours (using a Sanyo GA cell). If I go up to 2300 lumens, it will go up that high, regardless of the battery voltage. And when going downhill on gravel or dirt, I want that full 2300 lumens.

You need a light with a good boost driver if you want regulated output. For me, that’s very important when cycling. I don’t want to start out at 700 lumens, only to have it gradually dim to 400 lumens over my ride.

In UK/EU there are strict regulations about bike lights and reflectors, the German ones being the tightest.

They have been drawn up for good reason, with a lot of study. We ride bikes a lot more than in some other regions and have some experience of how to do it properly, on the road, mixed with faster transport.

If you don’t have at least a legal front and rear light with certification markings, and a full set of reflectors including pedals, then get wiped out by a motor vehicle, the insurers will probably persuade the court to reduce compensation by 50%

Other EU countries have a blanket policy, any such collision is always the drivers fault, no matter how stupidly the cyclist has behaved.

My point being that an A6 or FW3A is never going to be a suitable cycle light. Fundamental point, it doesn’t emit anything 90 degrees sideways, crucial to avoid side-road car main-road bike collisions (sorry mate, I didn’t see you as we say).

And the A6 etc. bikelight flashy mode is illegal here (detail: “The 2005 RVLR amendment meant that it was now legal to have a flashing light on a pedal cycle, provided it flashed between 60 and 240 times per minute (1 – 4Hz).”

To protect photosensitive epileptics.

I was sent a couple of extreme power “bike lights” by Thorfire to evaluate, but had to explain to them that whilst great for off-road, they would never be legal on-road anywhere in UK/EU, and they would have to get suitable certification. They were really good, but that project never went further.

In UK/EU there are strict regulations about bike lights and reflectors, the German ones being the tightest.

They have been drawn up for good reason, with a lot of study. We ride bikes a lot more than in some other regions and have some experience of how to do it properly, on the road, mixed with faster transport.

If you don’t have at least a legal front and rear light with certification markings, and a full set of reflectors including pedals, then get wiped out by a motor vehicle, the insurers will probably persuade the court to reduce compensation by 50%

Other EU countries have a blanket policy, any such collision is always the drivers fault, no matter how stupidly the cyclist has behaved.

My point being that an A6 or FW3A is never going to be a suitable cycle light. Fundamental point, it doesn’t emit anything 90 degrees sideways, crucial to avoid side-road car main-road bike collisions (sorry mate, I didn’t see you as we say).

And the A6 etc. bikelight flashy mode is illegal here (detail: “The 2005 RVLR amendment meant that it was now legal to have a flashing light on a pedal cycle, provided it flashed between 60 and 240 times per minute (1 – 4Hz).”

To protect photosensitive epileptics.

I was sent a couple of extreme power “bike lights” by Thorfire to evaluate, but had to explain to them that whilst great for off-road, they would never be legal on-road anywhere in UK/EU, and they would have to get suitable certification. They were really good, but that project never went further.

In UK/EU there are strict regulations about bike lights and reflectors, the German ones being the tightest.

The German regulations require that bikes use lights powered by a dynamo rather than a battery, unless the bike is under a certain weight and presumably for racing. They also require that the dynamo output 6 volts, which is oddly specific. I’m not sure these regulations are actually all that well-considered.

I do think a bike light for on-road use should have suitable optics, usually with hard cutoffs. The 10511 is absolutely not that. The 10510 elliptical optic might work OK for a bike light. Time spent in regulation with 7135s depends on forward voltage, which is lower for the same output with a triple. Of the possible emitters, the 219C has the lowest forward voltage.

Of course they were (and I enjoy them), but not appropriate for road-use and never going to be certified.

Limited market here, riding off-road at night ? Few bike shops would carry them without certification, even “under the counter”.

In UK you can have them (or anything) on you’re bike as long as you also have legal lights for on the road.

The UI was not suitable, just a circular cycle, so if using them on the road it took multiple button presses to dim them down or turn off. Not what you want to be doing when trying not to dazzle oncoming, and keep your hands on the handlebars and brake levers. Whilst riding fast.

Great off-road, but that’s specialist. The fashion here is MAMIL (middle aged men (or matrons) in Lycra, on sport road bikes. They don’t usually ride in the dark.

And ultra-light, just the bare minimum legal stuff, with a couple of tiny lights in case you get caught-out. Plus a GoPro on your helmet to record any bad behaviour by motorists. Motorists have dashcams too, for similar reasons.

Other EU countries use bikes for everyday transport, quite different, I wish we could reach that stage soon.